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                    程序结构
            
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                    类型
            
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                    常量
            
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                    结构体
            
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                    JSON
            
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                    文本和HTML模板
            
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                    函数
            
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                    函数值
            
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                    匿名函数
            
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                    可变参数
            
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                    Deferred函数
            
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                    Panic异常
            
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                    Recover捕获异常
            
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                    方法
            
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                    方法声明
            
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                    基于指针对象的方法
            
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                    通过嵌入结构体来扩展类型
            
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                    方法值和方法表达式
            
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                    示例: Bit数组
            
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                    封装
            
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                    接口
            
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                    接口是合约
            
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                    接口类型
            
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                    实现接口的条件
            
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                    flag.Value接口
            
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                    接口值
            
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                    sort.Interface接口
            
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                    http.Handler接口
            
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                    error接口
            
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                    示例: 表达式求值
            
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                    类型断言
            
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                    基于类型断言识别错误类型
            
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        <li class="chapter " data-level="1.8.12" data-path="../ch7/ch7-12.html">
            
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                    通过类型断言查询接口
            
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                    类型分支
            
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                    示例: 基于标记的XML解码
            
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                    补充几点
            
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                    Goroutines和Channels
            
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                    Goroutines
            
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                    示例: 并发的Clock服务
            
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        <li class="chapter " data-level="1.9.3" data-path="../ch8/ch8-03.html">
            
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                    示例: 并发的Echo服务
            
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                    Channels
            
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        <li class="chapter " data-level="1.9.5" data-path="../ch8/ch8-05.html">
            
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                    并发的循环
            
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        <li class="chapter " data-level="1.9.6" data-path="../ch8/ch8-06.html">
            
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                    示例: 并发的Web爬虫
            
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        <li class="chapter " data-level="1.9.7" data-path="../ch8/ch8-07.html">
            
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                    基于select的多路复用
            
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        <li class="chapter " data-level="1.9.8" data-path="../ch8/ch8-08.html">
            
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                    示例: 并发的目录遍历
            
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        <li class="chapter " data-level="1.9.9" data-path="../ch8/ch8-09.html">
            
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                    并发的退出
            
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        <li class="chapter " data-level="1.9.10" data-path="../ch8/ch8-10.html">
            
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                    示例: 聊天服务
            
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        <li class="chapter " data-level="1.10" data-path="../ch9/ch9.html">
            
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                    基于共享变量的并发
            
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                    竞争条件
            
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        <li class="chapter " data-level="1.10.2" data-path="../ch9/ch9-02.html">
            
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                    sync.Mutex互斥锁
            
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        <li class="chapter " data-level="1.10.3" data-path="../ch9/ch9-03.html">
            
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                    sync.RWMutex读写锁
            
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        <li class="chapter " data-level="1.10.4" data-path="../ch9/ch9-04.html">
            
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                    内存同步
            
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        <li class="chapter " data-level="1.10.5" data-path="../ch9/ch9-05.html">
            
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                    sync.Once惰性初始化
            
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                    示例: 编码S表达式
            
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                    通过reflect.Value修改值
            
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                    获取结构体字段标签
            
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                                <h2 id="132-unsafepointer">13.2. unsafe.Pointer</h2>
<p>&#x5927;&#x591A;&#x6570;&#x6307;&#x9488;&#x7C7B;&#x578B;&#x4F1A;&#x5199;&#x6210;<code>*T</code>&#xFF0C;&#x8868;&#x793A;&#x662F;&#x201C;&#x4E00;&#x4E2A;&#x6307;&#x5411;T&#x7C7B;&#x578B;&#x53D8;&#x91CF;&#x7684;&#x6307;&#x9488;&#x201D;&#x3002;unsafe.Pointer&#x662F;&#x7279;&#x522B;&#x5B9A;&#x4E49;&#x7684;&#x4E00;&#x79CD;&#x6307;&#x9488;&#x7C7B;&#x578B;&#xFF08;&#x8BD1;&#x6CE8;&#xFF1A;&#x7C7B;&#x4F3C;C&#x8BED;&#x8A00;&#x4E2D;&#x7684;<code>void*</code>&#x7C7B;&#x578B;&#x7684;&#x6307;&#x9488;&#xFF09;&#xFF0C;&#x5B83;&#x53EF;&#x4EE5;&#x5305;&#x542B;&#x4EFB;&#x610F;&#x7C7B;&#x578B;&#x53D8;&#x91CF;&#x7684;&#x5730;&#x5740;&#x3002;&#x5F53;&#x7136;&#xFF0C;&#x6211;&#x4EEC;&#x4E0D;&#x53EF;&#x4EE5;&#x76F4;&#x63A5;&#x901A;&#x8FC7;<code>*p</code>&#x6765;&#x83B7;&#x53D6;unsafe.Pointer&#x6307;&#x9488;&#x6307;&#x5411;&#x7684;&#x771F;&#x5B9E;&#x53D8;&#x91CF;&#x7684;&#x503C;&#xFF0C;&#x56E0;&#x4E3A;&#x6211;&#x4EEC;&#x5E76;&#x4E0D;&#x77E5;&#x9053;&#x53D8;&#x91CF;&#x7684;&#x5177;&#x4F53;&#x7C7B;&#x578B;&#x3002;&#x548C;&#x666E;&#x901A;&#x6307;&#x9488;&#x4E00;&#x6837;&#xFF0C;unsafe.Pointer&#x6307;&#x9488;&#x4E5F;&#x662F;&#x53EF;&#x4EE5;&#x6BD4;&#x8F83;&#x7684;&#xFF0C;&#x5E76;&#x4E14;&#x652F;&#x6301;&#x548C;nil&#x5E38;&#x91CF;&#x6BD4;&#x8F83;&#x5224;&#x65AD;&#x662F;&#x5426;&#x4E3A;&#x7A7A;&#x6307;&#x9488;&#x3002;</p>
<p>&#x4E00;&#x4E2A;&#x666E;&#x901A;&#x7684;<code>*T</code>&#x7C7B;&#x578B;&#x6307;&#x9488;&#x53EF;&#x4EE5;&#x88AB;&#x8F6C;&#x5316;&#x4E3A;unsafe.Pointer&#x7C7B;&#x578B;&#x6307;&#x9488;&#xFF0C;&#x5E76;&#x4E14;&#x4E00;&#x4E2A;unsafe.Pointer&#x7C7B;&#x578B;&#x6307;&#x9488;&#x4E5F;&#x53EF;&#x4EE5;&#x88AB;&#x8F6C;&#x56DE;&#x666E;&#x901A;&#x7684;&#x6307;&#x9488;&#xFF0C;&#x88AB;&#x8F6C;&#x56DE;&#x666E;&#x901A;&#x7684;&#x6307;&#x9488;&#x7C7B;&#x578B;&#x5E76;&#x4E0D;&#x9700;&#x8981;&#x548C;&#x539F;&#x59CB;&#x7684;<code>*T</code>&#x7C7B;&#x578B;&#x76F8;&#x540C;&#x3002;&#x901A;&#x8FC7;&#x5C06;<code>*float64</code>&#x7C7B;&#x578B;&#x6307;&#x9488;&#x8F6C;&#x5316;&#x4E3A;<code>*uint64</code>&#x7C7B;&#x578B;&#x6307;&#x9488;&#xFF0C;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x67E5;&#x770B;&#x4E00;&#x4E2A;&#x6D6E;&#x70B9;&#x6570;&#x53D8;&#x91CF;&#x7684;&#x4F4D;&#x6A21;&#x5F0F;&#x3002;</p>
<pre><code class="lang-Go"><span class="hljs-keyword">package</span> math

<span class="hljs-keyword">func</span> Float64bits(f <span class="hljs-keyword">float64</span>) <span class="hljs-keyword">uint64</span> { <span class="hljs-keyword">return</span> *(*<span class="hljs-keyword">uint64</span>)(unsafe.Pointer(&amp;f)) }

fmt.Printf(<span class="hljs-string">&quot;%#016x\n&quot;</span>, Float64bits(<span class="hljs-number">1.0</span>)) <span class="hljs-comment">// &quot;0x3ff0000000000000&quot;</span>
</code></pre>
<p>&#x901A;&#x8FC7;&#x8F6C;&#x4E3A;&#x65B0;&#x7C7B;&#x578B;&#x6307;&#x9488;&#xFF0C;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x66F4;&#x65B0;&#x6D6E;&#x70B9;&#x6570;&#x7684;&#x4F4D;&#x6A21;&#x5F0F;&#x3002;&#x901A;&#x8FC7;&#x4F4D;&#x6A21;&#x5F0F;&#x64CD;&#x4F5C;&#x6D6E;&#x70B9;&#x6570;&#x662F;&#x53EF;&#x4EE5;&#x7684;&#xFF0C;&#x4F46;&#x662F;&#x66F4;&#x91CD;&#x8981;&#x7684;&#x610F;&#x4E49;&#x662F;&#x6307;&#x9488;&#x8F6C;&#x6362;&#x8BED;&#x6CD5;&#x8BA9;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x5728;&#x4E0D;&#x7834;&#x574F;&#x7C7B;&#x578B;&#x7CFB;&#x7EDF;&#x7684;&#x524D;&#x63D0;&#x4E0B;&#x5411;&#x5185;&#x5B58;&#x5199;&#x5165;&#x4EFB;&#x610F;&#x7684;&#x503C;&#x3002;</p>
<p>&#x4E00;&#x4E2A;unsafe.Pointer&#x6307;&#x9488;&#x4E5F;&#x53EF;&#x4EE5;&#x88AB;&#x8F6C;&#x5316;&#x4E3A;uintptr&#x7C7B;&#x578B;&#xFF0C;&#x7136;&#x540E;&#x4FDD;&#x5B58;&#x5230;&#x6307;&#x9488;&#x578B;&#x6570;&#x503C;&#x53D8;&#x91CF;&#x4E2D;&#xFF08;&#x8BD1;&#x6CE8;&#xFF1A;&#x8FD9;&#x53EA;&#x662F;&#x548C;&#x5F53;&#x524D;&#x6307;&#x9488;&#x76F8;&#x540C;&#x7684;&#x4E00;&#x4E2A;&#x6570;&#x5B57;&#x503C;&#xFF0C;&#x5E76;&#x4E0D;&#x662F;&#x4E00;&#x4E2A;&#x6307;&#x9488;&#xFF09;&#xFF0C;&#x7136;&#x540E;&#x7528;&#x4EE5;&#x505A;&#x5FC5;&#x8981;&#x7684;&#x6307;&#x9488;&#x6570;&#x503C;&#x8FD0;&#x7B97;&#x3002;&#xFF08;&#x7B2C;&#x4E09;&#x7AE0;&#x5185;&#x5BB9;&#xFF0C;uintptr&#x662F;&#x4E00;&#x4E2A;&#x65E0;&#x7B26;&#x53F7;&#x7684;&#x6574;&#x578B;&#x6570;&#xFF0C;&#x8DB3;&#x4EE5;&#x4FDD;&#x5B58;&#x4E00;&#x4E2A;&#x5730;&#x5740;&#xFF09;&#x8FD9;&#x79CD;&#x8F6C;&#x6362;&#x867D;&#x7136;&#x4E5F;&#x662F;&#x53EF;&#x9006;&#x7684;&#xFF0C;&#x4F46;&#x662F;&#x5C06;uintptr&#x8F6C;&#x4E3A;unsafe.Pointer&#x6307;&#x9488;&#x53EF;&#x80FD;&#x4F1A;&#x7834;&#x574F;&#x7C7B;&#x578B;&#x7CFB;&#x7EDF;&#xFF0C;&#x56E0;&#x4E3A;&#x5E76;&#x4E0D;&#x662F;&#x6240;&#x6709;&#x7684;&#x6570;&#x5B57;&#x90FD;&#x662F;&#x6709;&#x6548;&#x7684;&#x5185;&#x5B58;&#x5730;&#x5740;&#x3002;</p>
<p>&#x8BB8;&#x591A;&#x5C06;unsafe.Pointer&#x6307;&#x9488;&#x8F6C;&#x4E3A;&#x539F;&#x751F;&#x6570;&#x5B57;&#xFF0C;&#x7136;&#x540E;&#x518D;&#x8F6C;&#x56DE;&#x4E3A;unsafe.Pointer&#x7C7B;&#x578B;&#x6307;&#x9488;&#x7684;&#x64CD;&#x4F5C;&#x4E5F;&#x662F;&#x4E0D;&#x5B89;&#x5168;&#x7684;&#x3002;&#x6BD4;&#x5982;&#x4E0B;&#x9762;&#x7684;&#x4F8B;&#x5B50;&#x9700;&#x8981;&#x5C06;&#x53D8;&#x91CF;x&#x7684;&#x5730;&#x5740;&#x52A0;&#x4E0A;b&#x5B57;&#x6BB5;&#x5730;&#x5740;&#x504F;&#x79FB;&#x91CF;&#x8F6C;&#x5316;&#x4E3A;<code>*int16</code>&#x7C7B;&#x578B;&#x6307;&#x9488;&#xFF0C;&#x7136;&#x540E;&#x901A;&#x8FC7;&#x8BE5;&#x6307;&#x9488;&#x66F4;&#x65B0;x.b&#xFF1A;</p>
<p><u><i>gopl.io/ch13/unsafeptr</i></u></p>
<pre><code class="lang-Go"><span class="hljs-keyword">var</span> x <span class="hljs-keyword">struct</span> {
    a <span class="hljs-keyword">bool</span>
    b <span class="hljs-keyword">int16</span>
    c []<span class="hljs-keyword">int</span>
}

<span class="hljs-comment">// &#x548C; pb := &amp;x.b &#x7B49;&#x4EF7;</span>
pb := (*<span class="hljs-keyword">int16</span>)(unsafe.Pointer(
    <span class="hljs-keyword">uintptr</span>(unsafe.Pointer(&amp;x)) + unsafe.Offsetof(x.b)))
*pb = <span class="hljs-number">42</span>
fmt.Println(x.b) <span class="hljs-comment">// &quot;42&quot;</span>
</code></pre>
<p>&#x4E0A;&#x9762;&#x7684;&#x5199;&#x6CD5;&#x5C3D;&#x7BA1;&#x5F88;&#x7E41;&#x7410;&#xFF0C;&#x4F46;&#x5728;&#x8FD9;&#x91CC;&#x5E76;&#x4E0D;&#x662F;&#x4E00;&#x4EF6;&#x574F;&#x4E8B;&#xFF0C;&#x56E0;&#x4E3A;&#x8FD9;&#x4E9B;&#x529F;&#x80FD;&#x5E94;&#x8BE5;&#x5F88;&#x8C28;&#x614E;&#x5730;&#x4F7F;&#x7528;&#x3002;&#x4E0D;&#x8981;&#x8BD5;&#x56FE;&#x5F15;&#x5165;&#x4E00;&#x4E2A;uintptr&#x7C7B;&#x578B;&#x7684;&#x4E34;&#x65F6;&#x53D8;&#x91CF;&#xFF0C;&#x56E0;&#x4E3A;&#x5B83;&#x53EF;&#x80FD;&#x4F1A;&#x7834;&#x574F;&#x4EE3;&#x7801;&#x7684;&#x5B89;&#x5168;&#x6027;&#xFF08;&#x8BD1;&#x6CE8;&#xFF1A;&#x8FD9;&#x662F;&#x771F;&#x6B63;&#x53EF;&#x4EE5;&#x4F53;&#x4F1A;unsafe&#x5305;&#x4E3A;&#x4F55;&#x4E0D;&#x5B89;&#x5168;&#x7684;&#x4F8B;&#x5B50;&#xFF09;&#x3002;&#x4E0B;&#x9762;&#x6BB5;&#x4EE3;&#x7801;&#x662F;&#x9519;&#x8BEF;&#x7684;&#xFF1A;</p>
<pre><code class="lang-Go"><span class="hljs-comment">// <span class="hljs-doctag">NOTE:</span> subtly incorrect!</span>
tmp := <span class="hljs-keyword">uintptr</span>(unsafe.Pointer(&amp;x)) + unsafe.Offsetof(x.b)
pb := (*<span class="hljs-keyword">int16</span>)(unsafe.Pointer(tmp))
*pb = <span class="hljs-number">42</span>
</code></pre>
<p>&#x4EA7;&#x751F;&#x9519;&#x8BEF;&#x7684;&#x539F;&#x56E0;&#x5F88;&#x5FAE;&#x5999;&#x3002;&#x6709;&#x65F6;&#x5019;&#x5783;&#x573E;&#x56DE;&#x6536;&#x5668;&#x4F1A;&#x79FB;&#x52A8;&#x4E00;&#x4E9B;&#x53D8;&#x91CF;&#x4EE5;&#x964D;&#x4F4E;&#x5185;&#x5B58;&#x788E;&#x7247;&#x7B49;&#x95EE;&#x9898;&#x3002;&#x8FD9;&#x7C7B;&#x5783;&#x573E;&#x56DE;&#x6536;&#x5668;&#x88AB;&#x79F0;&#x4E3A;&#x79FB;&#x52A8;GC&#x3002;&#x5F53;&#x4E00;&#x4E2A;&#x53D8;&#x91CF;&#x88AB;&#x79FB;&#x52A8;&#xFF0C;&#x6240;&#x6709;&#x7684;&#x4FDD;&#x5B58;&#x8BE5;&#x53D8;&#x91CF;&#x65E7;&#x5730;&#x5740;&#x7684;&#x6307;&#x9488;&#x5FC5;&#x987B;&#x540C;&#x65F6;&#x88AB;&#x66F4;&#x65B0;&#x4E3A;&#x53D8;&#x91CF;&#x79FB;&#x52A8;&#x540E;&#x7684;&#x65B0;&#x5730;&#x5740;&#x3002;&#x4ECE;&#x5783;&#x573E;&#x6536;&#x96C6;&#x5668;&#x7684;&#x89C6;&#x89D2;&#x6765;&#x770B;&#xFF0C;&#x4E00;&#x4E2A;unsafe.Pointer&#x662F;&#x4E00;&#x4E2A;&#x6307;&#x5411;&#x53D8;&#x91CF;&#x7684;&#x6307;&#x9488;&#xFF0C;&#x56E0;&#x6B64;&#x5F53;&#x53D8;&#x91CF;&#x88AB;&#x79FB;&#x52A8;&#x65F6;&#x5BF9;&#x5E94;&#x7684;&#x6307;&#x9488;&#x4E5F;&#x5FC5;&#x987B;&#x88AB;&#x66F4;&#x65B0;&#xFF1B;&#x4F46;&#x662F;uintptr&#x7C7B;&#x578B;&#x7684;&#x4E34;&#x65F6;&#x53D8;&#x91CF;&#x53EA;&#x662F;&#x4E00;&#x4E2A;&#x666E;&#x901A;&#x7684;&#x6570;&#x5B57;&#xFF0C;&#x6240;&#x4EE5;&#x5176;&#x503C;&#x4E0D;&#x5E94;&#x8BE5;&#x88AB;&#x6539;&#x53D8;&#x3002;&#x4E0A;&#x9762;&#x9519;&#x8BEF;&#x7684;&#x4EE3;&#x7801;&#x56E0;&#x4E3A;&#x5F15;&#x5165;&#x4E00;&#x4E2A;&#x975E;&#x6307;&#x9488;&#x7684;&#x4E34;&#x65F6;&#x53D8;&#x91CF;tmp&#xFF0C;&#x5BFC;&#x81F4;&#x5783;&#x573E;&#x6536;&#x96C6;&#x5668;&#x65E0;&#x6CD5;&#x6B63;&#x786E;&#x8BC6;&#x522B;&#x8FD9;&#x4E2A;&#x662F;&#x4E00;&#x4E2A;&#x6307;&#x5411;&#x53D8;&#x91CF;x&#x7684;&#x6307;&#x9488;&#x3002;&#x5F53;&#x7B2C;&#x4E8C;&#x4E2A;&#x8BED;&#x53E5;&#x6267;&#x884C;&#x65F6;&#xFF0C;&#x53D8;&#x91CF;x&#x53EF;&#x80FD;&#x5DF2;&#x7ECF;&#x88AB;&#x8F6C;&#x79FB;&#xFF0C;&#x8FD9;&#x65F6;&#x5019;&#x4E34;&#x65F6;&#x53D8;&#x91CF;tmp&#x4E5F;&#x5C31;&#x4E0D;&#x518D;&#x662F;&#x73B0;&#x5728;&#x7684;<code>&amp;x.b</code>&#x5730;&#x5740;&#x3002;&#x7B2C;&#x4E09;&#x4E2A;&#x5411;&#x4E4B;&#x524D;&#x65E0;&#x6548;&#x5730;&#x5740;&#x7A7A;&#x95F4;&#x7684;&#x8D4B;&#x503C;&#x8BED;&#x53E5;&#x5C06;&#x5F7B;&#x5E95;&#x6467;&#x6BC1;&#x6574;&#x4E2A;&#x7A0B;&#x5E8F;&#xFF01;</p>
<p>&#x8FD8;&#x6709;&#x5F88;&#x591A;&#x7C7B;&#x4F3C;&#x539F;&#x56E0;&#x5BFC;&#x81F4;&#x7684;&#x9519;&#x8BEF;&#x3002;&#x4F8B;&#x5982;&#x8FD9;&#x6761;&#x8BED;&#x53E5;&#xFF1A;</p>
<pre><code class="lang-Go">pT := <span class="hljs-keyword">uintptr</span>(unsafe.Pointer(<span class="hljs-built_in">new</span>(T))) <span class="hljs-comment">// &#x63D0;&#x793A;: &#x9519;&#x8BEF;!</span>
</code></pre>
<p>&#x8FD9;&#x91CC;&#x5E76;&#x6CA1;&#x6709;&#x6307;&#x9488;&#x5F15;&#x7528;<code>new</code>&#x65B0;&#x521B;&#x5EFA;&#x7684;&#x53D8;&#x91CF;&#xFF0C;&#x56E0;&#x6B64;&#x8BE5;&#x8BED;&#x53E5;&#x6267;&#x884C;&#x5B8C;&#x6210;&#x4E4B;&#x540E;&#xFF0C;&#x5783;&#x573E;&#x6536;&#x96C6;&#x5668;&#x6709;&#x6743;&#x9A6C;&#x4E0A;&#x56DE;&#x6536;&#x5176;&#x5185;&#x5B58;&#x7A7A;&#x95F4;&#xFF0C;&#x6240;&#x4EE5;&#x8FD4;&#x56DE;&#x7684;pT&#x5C06;&#x662F;&#x65E0;&#x6548;&#x7684;&#x5730;&#x5740;&#x3002;</p>
<p>&#x867D;&#x7136;&#x76EE;&#x524D;&#x7684;Go&#x8BED;&#x8A00;&#x5B9E;&#x73B0;&#x8FD8;&#x6CA1;&#x6709;&#x4F7F;&#x7528;&#x79FB;&#x52A8;GC&#xFF08;&#x8BD1;&#x6CE8;&#xFF1A;&#x672A;&#x6765;&#x53EF;&#x80FD;&#x5B9E;&#x73B0;&#xFF09;&#xFF0C;&#x4F46;&#x8FD9;&#x4E0D;&#x8BE5;&#x662F;&#x7F16;&#x5199;&#x9519;&#x8BEF;&#x4EE3;&#x7801;&#x4FA5;&#x5E78;&#x7684;&#x7406;&#x7531;&#xFF1A;&#x5F53;&#x524D;&#x7684;Go&#x8BED;&#x8A00;&#x5B9E;&#x73B0;&#x5DF2;&#x7ECF;&#x6709;&#x79FB;&#x52A8;&#x53D8;&#x91CF;&#x7684;&#x573A;&#x666F;&#x3002;&#x5728;5.2&#x8282;&#x6211;&#x4EEC;&#x63D0;&#x5230;goroutine&#x7684;&#x6808;&#x662F;&#x6839;&#x636E;&#x9700;&#x8981;&#x52A8;&#x6001;&#x589E;&#x957F;&#x7684;&#x3002;&#x5F53;&#x53D1;&#x751F;&#x6808;&#x52A8;&#x6001;&#x589E;&#x957F;&#x7684;&#x65F6;&#x5019;&#xFF0C;&#x539F;&#x6765;&#x6808;&#x4E2D;&#x7684;&#x6240;&#x6709;&#x53D8;&#x91CF;&#x53EF;&#x80FD;&#x9700;&#x8981;&#x88AB;&#x79FB;&#x52A8;&#x5230;&#x65B0;&#x7684;&#x66F4;&#x5927;&#x7684;&#x6808;&#x4E2D;&#xFF0C;&#x6240;&#x4EE5;&#x6211;&#x4EEC;&#x5E76;&#x4E0D;&#x80FD;&#x786E;&#x4FDD;&#x53D8;&#x91CF;&#x7684;&#x5730;&#x5740;&#x5728;&#x6574;&#x4E2A;&#x4F7F;&#x7528;&#x5468;&#x671F;&#x5185;&#x662F;&#x4E0D;&#x53D8;&#x7684;&#x3002;</p>
<p>&#x5728;&#x7F16;&#x5199;&#x672C;&#x6587;&#x65F6;&#xFF0C;&#x8FD8;&#x6CA1;&#x6709;&#x6E05;&#x6670;&#x7684;&#x539F;&#x5219;&#x6765;&#x6307;&#x5F15;Go&#x7A0B;&#x5E8F;&#x5458;&#xFF0C;&#x4EC0;&#x4E48;&#x6837;&#x7684;unsafe.Pointer&#x548C;uintptr&#x7684;&#x8F6C;&#x6362;&#x662F;&#x4E0D;&#x5B89;&#x5168;&#x7684;&#xFF08;&#x53C2;&#x8003; <a href="https://github.com/golang/go/issues/7192" target="_blank">Issue7192</a> &#xFF09;. &#x8BD1;&#x6CE8;: &#x8BE5;&#x95EE;&#x9898;&#x5DF2;&#x7ECF;&#x5173;&#x95ED;&#xFF09;&#xFF0C;&#x56E0;&#x6B64;&#x6211;&#x4EEC;&#x5F3A;&#x70C8;&#x5EFA;&#x8BAE;&#x6309;&#x7167;&#x6700;&#x574F;&#x7684;&#x65B9;&#x5F0F;&#x5904;&#x7406;&#x3002;&#x5C06;&#x6240;&#x6709;&#x5305;&#x542B;&#x53D8;&#x91CF;&#x5730;&#x5740;&#x7684;uintptr&#x7C7B;&#x578B;&#x53D8;&#x91CF;&#x5F53;&#x4F5C;BUG&#x5904;&#x7406;&#xFF0C;&#x540C;&#x65F6;&#x51CF;&#x5C11;&#x4E0D;&#x5FC5;&#x8981;&#x7684;unsafe.Pointer&#x7C7B;&#x578B;&#x5230;uintptr&#x7C7B;&#x578B;&#x7684;&#x8F6C;&#x6362;&#x3002;&#x5728;&#x7B2C;&#x4E00;&#x4E2A;&#x4F8B;&#x5B50;&#x4E2D;&#xFF0C;&#x6709;&#x4E09;&#x4E2A;&#x8F6C;&#x6362;&#x2014;&#x2014;&#x5B57;&#x6BB5;&#x504F;&#x79FB;&#x91CF;&#x5230;uintptr&#x7684;&#x8F6C;&#x6362;&#x548C;&#x8F6C;&#x56DE;unsafe.Pointer&#x7C7B;&#x578B;&#x7684;&#x64CD;&#x4F5C;&#x2014;&#x2014;&#x6240;&#x6709;&#x7684;&#x8F6C;&#x6362;&#x5168;&#x5728;&#x4E00;&#x4E2A;&#x8868;&#x8FBE;&#x5F0F;&#x5B8C;&#x6210;&#x3002;</p>
<p>&#x5F53;&#x8C03;&#x7528;&#x4E00;&#x4E2A;&#x5E93;&#x51FD;&#x6570;&#xFF0C;&#x5E76;&#x4E14;&#x8FD4;&#x56DE;&#x7684;&#x662F;uintptr&#x7C7B;&#x578B;&#x5730;&#x5740;&#x65F6;&#xFF08;&#x8BD1;&#x6CE8;&#xFF1A;&#x666E;&#x901A;&#x65B9;&#x6CD5;&#x5B9E;&#x73B0;&#x7684;&#x51FD;&#x6570;&#x5C3D;&#x91CF;&#x4E0D;&#x8981;&#x8FD4;&#x56DE;&#x8BE5;&#x7C7B;&#x578B;&#x3002;&#x4E0B;&#x9762;&#x4F8B;&#x5B50;&#x662F;reflect&#x5305;&#x7684;&#x51FD;&#x6570;&#xFF0C;reflect&#x5305;&#x548C;unsafe&#x5305;&#x4E00;&#x6837;&#x90FD;&#x662F;&#x91C7;&#x7528;&#x7279;&#x6B8A;&#x6280;&#x672F;&#x5B9E;&#x73B0;&#x7684;&#xFF0C;&#x7F16;&#x8BD1;&#x5668;&#x53EF;&#x80FD;&#x7ED9;&#x5B83;&#x4EEC;&#x5F00;&#x4E86;&#x540E;&#x95E8;&#xFF09;&#xFF0C;&#x6BD4;&#x5982;&#x4E0B;&#x9762;&#x53CD;&#x5C04;&#x5305;&#x4E2D;&#x7684;&#x76F8;&#x5173;&#x51FD;&#x6570;&#xFF0C;&#x8FD4;&#x56DE;&#x7684;&#x7ED3;&#x679C;&#x5E94;&#x8BE5;&#x7ACB;&#x5373;&#x8F6C;&#x6362;&#x4E3A;unsafe.Pointer&#x4EE5;&#x786E;&#x4FDD;&#x6307;&#x9488;&#x6307;&#x5411;&#x7684;&#x662F;&#x76F8;&#x540C;&#x7684;&#x53D8;&#x91CF;&#x3002;</p>
<pre><code class="lang-Go"><span class="hljs-keyword">package</span> reflect

<span class="hljs-keyword">func</span> (Value) Pointer() <span class="hljs-keyword">uintptr</span>
<span class="hljs-keyword">func</span> (Value) UnsafeAddr() <span class="hljs-keyword">uintptr</span>
<span class="hljs-keyword">func</span> (Value) InterfaceData() [<span class="hljs-number">2</span>]<span class="hljs-keyword">uintptr</span> <span class="hljs-comment">// (index 1)</span>
</code></pre>

                                
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